Fluorescent compositions comprising diketopyrrolopyrroles

ABSTRACT

The present invention relates to compositions comprising a guest chromophore and a host chromophore, wherein the absorption spectrum of the guest chromophore overlaps with the fluorescence emission spectrum of the host chromophore, wherein the host chromophore is a diketopyrrolopyrrole having an absorption peak at 500 to 720 nm, preferably 500 to 600 nm, most preferred 520 to 580 nm and wherein the guest chromophore is a diketopyrrolopyrrole having an absorption peak at 500 to 720 nm, preferably 500 to 600 nm, most preferred 520 to 580 nm and their use for the preparation of inks, colorants, pigmented plastics for coatings, non-impact-printing material, color filters, cosmetics, polymeric ink particles, toners, dye lasers and electroluminescent devices. A luminescent device comprising a composition according to the present invention is high in the efficiency of electrical energy utilisation and high in luminance.

The present invention relates to fluorescent compositions comprising aguest chromophore and a host chromophore, wherein the absorptionspectrum of the guest chromophore overlaps with the fluorescenceemission spectrum of the host chromophore, wherein the host chromophoreis a diketopyrrolopyrrole having a photoluminescence emission peak at500 to 720 nm, preferably 500 to 600 nm, most preferred 520 to 580 nmand wherein the guest chromophore is a diketopyrrolopyrrole having anabsorption peak at 500 to 720 nm, preferably 500 to 600 nm, mostpreferred 520 to 580 nm and their use for the preparation of inks,colorants, pigmented plastics for coatings, non-impact-printingmaterial, color filters, cosmetics, polymeric ink particles, toners, dyelasers and electroluminescent devices. A luminescent device comprising acomposition according to the present invention is high in the efficiencyof electrical energy utilisation and high in luminance.

It is presently common to prepare organic electroluminescent (“EL”)devices which contain an organic fluorescent substance by a vacuumevaporation process, e.g. described in Appl. Phys. Lett., 51, 913(1987). In general, two types of such vacuum evaporation processes areapplied according to the constitution of light emitting material: aone-component type process and a two-component type (or “Host-Guesttype” or “binary system”) process (e.g. described in J. Appl. Phys., 65,3610 (1989)).

For emitting a light of red, green or blue color in a one-componentsystem, the light emitting materials themselves have to emit an intensefluorescence of red, green or blue color. Further, a vacuum evaporationprocess has to give a deposited film of uniform quality, and the filmthus formed has to be endowed with appropriate (“carrier”) mobility forpositive holes and/or electrons i.e. properties of a semiconductor.

Numerous materials emitting light in the green- or blue-colored regionare known.

JP-B2 2,749,407 (Pioneer Electron Corp. & Nippon Kayaku Co. Ltd.)describes as a light emitting materialN,N′-bis(2,5-di-tert.-butylphenyl)-3,4,9,10-perylenedicarboximide.However, its luminance is as low as 27 cd/m², which is insufficient forcommercial applications.

JP-A2 2,296,891 (Ricoh) claims an electroluminescent element comprisinga positive electrode, a negative electrode and one organic compoundlayer or a plurality of organic compound layers held between thepositive and negative electrodes, but no hole transporting substance. Atleast one layer of said organic compound layers is a layer containing apyrrolopyrrole compound represented by the following formula II″

wherein Y₁ and Y₂ independently from each other represent a substitutedor unsubstituted alkyl, cycloalkyl or aryl group, Y₃ and Y₄independently represent a hydrogen atom or a substituted orunsubstituted alkyl or aryl group, and X represents an oxygen or asulfur atom. Only four compounds are mentioned explicitly, namelywherein X stands for oxygen in all cases, and wherein (a) Y₃=Y₄=methyland Y₁=Y₂=p-tolyl, (b) Y₃=Y₄=methyl and Y₁=Y₂=hydrogen, (c)Y₃=Y₄=hydrogen and Y₁=Y₂=p-tolyl, and (d) Y₃=Y₄=Y₁=hydrogen andY₂=p-chlorophenyl. However, according to JP-A2 5,320,633 (see below), afollow-up study of the same inventors revealed that an emission of lightis only observed, if the DPP-compounds II″ are used together with othercompounds. This observation is supported by comparative example 2 ofJP-A2 5,320,633, which shows that no emission is observed, if DPP II″ isused alone, i.e. without the addition oftris(8-hydroxyquinolinato)aluminium (“Alq₃”).

JP-A2 5,320,633 (Sumitomo) claims an organic EL device having a lightemitting layer comprising a light emitting material in an amount of0.005 to 15 parts by weight of a DPP compound between a pair ofelectrodes, wherein at least one electrode being transparent orsemi-transparent. Although the main claim is silent about the use ofAlq₃, it is clear from the specification and the examples, especiallyfrom comparative example 2, that Alq₃ is an essential feature in theclaimed EL element or device.

JP-A2 9003448 (Toyo Ink) claims an organic EL element having between apair of electrodes a luminous layer containing a DPP compound aselectron-transporting material or an organic compound thin film layerincluding a luminous layer and an electron-injecting layer wherein theelectron-injecting layer contains a DPP compound as theelectron-transporting material. In addition, another EL element furthercomprising a hole-injecting layer is claimed. The disadvantage of theclaimed EL devices is that according to the examples always Alq₃ and aphenanthrene diamine (as hole-injecting material) have to be used.

EP-A 499,011 describes electroluminescent devices comprisingDPP-compounds. Particularly, in example 1 the DPP-derivative of formulaIII′

is disclosed.

WO 98/33862 describes the use of the DPP-compound of formula IV′

as a guest molecule in electroluminescent devices.

EP-A-1087005 relates to fluorescent diketbpyrrolopyrroles (“DPPs”) ofthe formula I′

wherein R_(1′) and R_(2′), independently from each other, stand forC₁-C₂₅-alkyl, allyl which can be substituted one to three times withC₁-C₃alkyl or Ar_(3′), —CR_(3′)R_(4′)—(CH₂)_(m)—Ar_(3′), wherein R_(3′)and R_(4′) independently from each other stand for hydrogen orC₁-C₄alkyl, or phenyl which can be substituted on to three times withC₁-C₃ alkyl, Ar_(3′) stands for phenyl or 1- or 2-naphthyl which can besubstituted one to three times with C₁-C₈alkyl, C₁-C₈alkoxy, halogen orphenyl, which can be substituted with C₁-C₈alkyl or C₁-C₈alkoxy one tothree times, and m′ stands for 0, 1, 2, 3 or 4, and wherein C₁-C₂₅-alkylor —CR_(3′)R_(4′)—(CH₂)_(m)—Ar_(3′), preferably C₁-C₂₅-alkyl, can besubstituted with a functional group capable of increasing the solubilityin water such as a tertiary amino group, —SO₃ ⁻, or PO₄ ²⁻, Ar₁ and Ar₂,independently from each other, stand for

wherein R₆′ and R₇′, independently from each other, stand for hydrogen,C₁-C₆alkyl, —NR₈′R₉′, —OR₁₀′, —S(O)_(n)R₈′, —Se(O)_(n)R₈′, or phenyl,which can be substituted one to three times with C₁-C₈alkyl orC₁-C₈alkoxy, but do not stand simultaneously for hydrogen, whereinR_(8′) and R_(9′), independently from each other, stand for hydrogen,C₁-C₂₅-alkyl, C₅-C₁₂-cycloalkyl, —CR_(3′)R_(4′)—(CH₂)_(m′)—Ph, R_(10′),wherein R₁₀′ stands for C₆-C₂₄-aryl, or a saturated or unsaturatedheterocyclic radical comprising five to seven ring atoms, wherein thering consists of carbon atoms and one to three hetero atoms selectedfrom the group consisting of nitrogen, oxygen and sulfur, wherein Ph,the aryl and heterocyclic radical can be substituted one to three timeswith C₁-C₈alkyl, C₁-C₈alkoxy, or halogen, or R_(8′) and R_(9′) stand for—C(∩)R_(10′), wherein R_(11′) can be C₁-C₂₅-alkyl, C₅-C₁₂-cycloalkyl,R_(10′), —OR₁₂′ or —NR_(13′)R_(14′), wherein R_(12′), R_(13′), andR_(14′), stand for C₁-C₂₅-alkyl, C₆-C₁₂-cycloalkyl, C₆-C₂₄-aryl, or asaturated or unsaturated heterocyclic radical comprising five to sevenring atoms, wherein the ring consists of carbon atoms and one to threehetero atoms selected from the group consisting of nitrogen, oxygen andsulfur, wherein the aryl and heterocyclic radical can be substituted oneto three times with C₁-C₈alkyl or C₁-C₈alkoxy, or —NR_(8′) R_(9′) standsfor a five- or six-membered heterocyclic radical in which R_(8′) andR_(9′) together stand for tetramethylene, pentamethylene,—CH₂—CH₂—O—CH₂—CH₂—, or —CH₂—CH₂—NR₅—CH₂—CH₂—, preferably—CH₂—CH₂—O—CH₂—CH₂—, and n′ stands for 0, 1, 2 or 3. The DPP compoundscan be used for the preparation of inks, colorants, pigmented plasticsfor coatings, non-impact-printing material, color filters, cosmetics, orfor the preparation of polymeric ink particles, toners, dye lasers andelectroluminescent devices.

EP-A-1087006 relates to an electroluminescent device comprising in thisorder (a) an anode, (b) a hole transporting layer, (c) a light-emittinglayer, (d) optionally an electron transporting layer and (e) a cathodeand a light-emitting substance, wherein the light-emitting substance isa diketopyrrolopyrrole (“DPP”) represented by formula 1′.

Further fluorescent DPP compounds and their use in electroluminescentdevices are disclosed in EP 01810636.

Surprisingly, it was found that luminescent devices, which are high inthe efficiency of electrical energy utilisation and high in luminance,can be obtained if specific combinations of DPP compounds are used aslight emitting substances.

Accordingly, the present invention relates to compositions comprising aguest chromophore and a host chromophore, wherein the absorptionspectrum of the guest chromophore overlaps with the fluorescenceemission spectrum of the host chromophore, wherein the host chromophoreis a diketopyrrolopyrrole having a photoluminescence emission peak at500 to 720 nm, preferably 500 to 600 nm, most preferred 520 to 580 nmand wherein the guest chromophore is a diketopyrrolopyrrole having anabsorption peak at 500 to 720 nm, preferably 500 to 600 nm, mostpreferred 520 to 580 nm

In a preferred embodiment, the present invention relates to compositionscomprising a diketopyrrolopyrrole (“DPP”) represented by formula I

and a DPP represented by formula II

wherein R¹, R², R³ and R⁴ independently from each other stand forC₁-C₂₅-alkyl, which can be substituted by fluorine, chlorine or bromine,CS-C₁₋₂-cycloalkyl or C₅-C₁₂-cycloalkyl which can be condensed one ortwo times by phenyl which can be substituted one to three times withC₁-C₄-alkyl, halogen, nitro or cyano, silyl, A⁵ or—CR¹¹R¹²—(CH₂)_(m)-A⁵, wherein R¹¹ and R¹² independently from each otherstand for hydrogen, fluorine, chlorine, bromine, cyano or C₁-C₄alkyl,which can be substituted by fluorine, chlorine or bromine, or phenylwhich can be substituted one to three times with C₁-C₃alkyl, A⁵ standsfor phenyl or 1- or 2-naphthyl which can be substituted one to threetimes with C₁-C₈alkyl, C₁-C₈alkoxy, halogen, nitro, cyano, phenyl, whichcan be substituted with C₁-C₈alkyl or C₁-C₈alkoxy one to three times,—NR¹³R¹⁴ wherein R¹³ and R¹⁴ represent hydrogen, C₁-C₂₅-alkyl,C₅-C₁₂-cycloalkyl or C₆-C₂₄-aryl, in particular phenyl or 1- or2-naphthyl which can be substituted one to three times with C₁-C₈alkyl,C₁-C₈alkoxy, halogen or cyano, or phenyl, which can be substituted withC₁-C₈alkyl or C₁-C₈alkoxy one to three times, and m stands for 0, 1, 2,3 or 4,

-   A¹ and A² independently from each other stand for    wherein-   R⁵, R⁶, R⁷ independently from each other stands for hydrogen,    C₁-C₂₅-alkyl, C₁-C₂₅-alkoxy, —OCR¹¹R¹²—(CH₂)_(m)-A⁵, cyano, halogen,    —OR¹⁰, —S(O)_(p)R¹³, or phenyl, which can be substituted one to    three times with C₁-C₈alkyl or C₁-C₈alkoxy, wherein R¹⁰ stands for    C₆-C₂₄-aryl, or a saturated or unsaturated heterocyclic radical    comprising five to seven ring atoms, wherein the ring consists of    carbon atoms and one to three hetero atoms selected from the group    consisting of nitrogen, oxygen and sulfur, R¹³ stands for    C₁-C₂₅-alkyl, C₅-C₁₂-cycloalkyl, —CR¹¹R¹²—(CH₂)_(m)—Ph, R¹⁵ stands    for C₆-C₂₄-aryl, p stands for 0, 1, 2 or 3 and n stands for 0, 1, 2,    3 or 4,-   A³ and A⁴ independently from each other stand for    wherein R⁸ and R⁹ independently from each other stand for hydrogen,    C₁-C₂₅-alkyl, C₅-C₁₂-cycloalkyl, —CR¹¹R¹²_(CH₂)_(m) A⁵, C₆-C₂₄-aryl,    in particular A¹, or a saturated or unsaturated heterocyclic radical    comprising five to seven ring atoms, wherein the ring consists of    carbon atoms and one to three hetero atoms selected from the group    consisting of nitrogen, oxygen and sulfur, and R¹⁶ and R¹⁷    independently from each other stand for hydrogen and C₆-C₂₄-aryl, in    particular phenyl; an electroluminescent device comprising the    above-mentioned composition and the use of the composition for    coloring a high molecular weight organic material, i.e. the use of    the composition for the preparation of inks, colorants, pigmented    plastics for coatings, non-impact-printing material, color filters,    cosmetics, polymeric ink particles, toners, dye lasers and    electroluminescent devices.

The present invention provides red or orange fluorescent compositionswith a high heat stability, a good solubility in polymers, hydrocarbonbased fuels, lubricants etc., a high light stability, and the ability tobe used in plastics, especially polyamides, without decomposition andloss of lightfastness, and in paints and with a high electroluminescent(EL) emission intensity.

R¹, R², R³ and R⁴ independently from each other stand for C₁-C₂₅-alkyl,preferably C₁-C₈alkyl, in particular n-butyl, tert.-butyl and neopentyl,O₅—C₁₋₂cycloalkyl or C₅-C₁₂-cycloalkyl which can be condensed one or twotimes by phenyl which can be substituted one to three times withC₁-C₄-alkyl, halogen and cyano, in particular cyclohexyl, which can besubstituted one to three times with C₁-C₈alkyl and/or C₁-C₈alkoxy, inparticular 2,6-di-isopropylcyclohexyl, or

silyl, in particular trimethylsilyl, A⁵ or —CR¹¹R¹² (CH₂)_(m)-A⁵,wherein R¹¹ and R¹² independently from each other stand for hydrogen orC₁-C₄alkyl, or phenyl which can be substituted one to three times withC₁-C₃alkyl, A⁵ stands for phenyl or 1- or 2-naphthyl which can besubstituted one to three times with C₁-C₈alkyl, C₁-C₈alkoxy, halogen,cyano, phenyl, which can be substituted with C₁-C₈alkyl or C₁-C₈alkoxyone to three times, or —NR¹³R¹⁴, wherein R¹³ and R¹⁴ representC₁-C₂₅-alkyl, C₅-C₁₂-cycloalkyl or C₆-C₂₄-aryl, in particular phenyl or1- or 2-naphthyl, which can be substituted one to three times withC₁-C₈alkyl, C₁-C₈alkoxy, halogen or cyano or phenyl, which can besubstituted with C₁-C₈alkyl or C₁-C₈alkoxy one to three times, inparticular 3,5-dimethylphenyl, 3,5-di-tert.-butylphenyl, 3-methylphenyland 2,6-di-isopropylphenyl, and m stands for 0, 1, 2, 3 or 4, inparticular 0 or 1.

Preferably R¹ and R² are independently of each other C₁-C₈alkyl,

or —CR¹¹R¹²-A⁵, wherein R¹¹ is hydrogen, R¹² is hydrogen, in particularmethyl or phenyl and A⁵ is

wherein R⁵, R⁶ and R⁷ are independently of each other hydrogen,C₁-C₄-alkyl, or halogen, in particular Br, wherein groups

wherein R⁵, R⁶ and R⁷ are hydrogen; R⁶ is CO—C₄-alkyl, phenyl or Br andR⁵ and R⁷ are hydrogen; R⁵ is C₁-C₄-alkyl and R⁶ and R⁷ are hydrogen; orR⁶ is hydrogen and R⁵ and R⁷ are C₁-C₄-alkyl are most preferred.

Preferably R³ and R⁴ are independently of each other C₁-C₈-alkyl or—CR¹¹R¹²-A⁵, wherein R¹¹ is hydrogen, R¹² is methyl or phenyl, inparticular hydrogen and A⁵ is

wherein R⁵, R⁶ and R⁷ are independently of each other hydrogen,C₁-C₄-alkyl, or CN, wherein groups

wherein R⁵, R⁶ and R⁷ are hydrogen; R⁶ is CN or C₁-C₄-alkyl and R⁵ andR⁷ are hydrogen, R⁵ and R⁶ are CN and R⁷ is hydrogen; R⁵ is C₁-C₄-alkyland R⁶ and R⁷ are hydrogen; or R⁶ is hydrogen and R⁵ and R⁷ areC₁-C₄-alkyl are most preferred.

The weight ratio of the DPP compound of the formula I to the DPPcompound of the formula II is in general 50:50 to 99.99:0.01, preferably90:10 to 99.99:0.01, more preferably 95:5 to 99.9:0.1, most preferably98:2 to 99.9:0.1.

The DPP compounds of the formula I and II are distinguished by thesubstituents A¹ and A² and A³ and A⁴, respectively.

A¹ and A² independently from each other stand for

wherein R⁵, R⁶, R⁷, n and R¹⁵ have the above-mentioned meanings.

If the phenyl or naphthyl substituent is substituted by a vinyl group,A¹ and A² independently from each other can stand for

wherein n is an integer of 1 to 4, in particular 1 or 2, R⁵ and R⁶independently from each other can stand for hydrogen, C₁-C₈alkyl orC₁-C₈alkoxy and R¹⁵ is C₆-C₂₄aryl, such as phenyl, 1-naphthyl,2-naphthyl, 4-biphenyl, phenanthryl, terphenyl, pyrenyl, 2- or9-fluorenyl or anthracenyl, preferably C₆-C₁₂aryl such as phenyl,1-naphthyl, 2-naphthyl, 4-biphenyl, which may be unsubstituted orsubstituted by C₁-C₈alkyl or C₁-C₈alkoxy, wherein groups of thefollowing formula are preferred:

If A¹ and A² independently from each other stand for

R⁵, R⁶ and R⁷ independently from each other stand for hydrogen,C₁-C₈-alkyl, C₁-C₈-alkoxy, —OCR¹¹R¹²—(CH₂)_(m)-A⁵, cyano, chloro, —OR¹⁰,or phenyl, which can be substituted one to three times with C₁-C₈alkylor C₁-C₈alkoxy, wherein R¹⁰ stands for C₆-C₂₄-aryl, such as phenyl,1-naphthyl or 2-naphthyl, R¹¹ and R¹² are hydrogen or C₁-C₄-alkyl, m is0 or 1, A⁵ is phenyl, 1-naphthyl or 2-naphthyl, wherein groups of thefollowing formula are preferred:

wherein R⁵ is C₁-C₈-alkyl.

In addition, DPP compounds of the formula I are preferred, wherein R¹and R² are C₁-C₂₅-alkyl, in particular C₁-C₂₅-alkyl, wherein all or partof the hydrogen atoms are replaced by fluorine atoms, a group—CR¹¹R¹²-A⁵, wherein R¹¹ is hydrogen or C₁₋₄-alkyl, in particularmethyl, R¹² is CF₃ or F, and A⁵ is phenyl, or a group —CR¹¹R¹²-A⁵,wherein R¹¹ is hydrogen, R¹² is C₁₋₄alkyl, in particular methyl, A⁵ is agroup

wherein R⁶ is fluorine, chlorine, bromine, preferably cyano or nitro.

The wording “C₁-C₂₅-alkyl, which are substituted by fluorine” compriseslinear or branched C₁-C₂₅-alkyl groups wherein all or a part of thehydrogen atoms are replaced by fluorine atoms. Examples of such groupsare —CH₂F, —CHF₂, —CF₃, FH₂CCH₂—, FH₂CCHF—, F₂HCCH₂—, F₂HCCHF—, F₃CCH₂—,F₂HCCF₂—, F₃CCHF—, F₃CCF₂—, CF₃CF₂CF₂—, CF₃CF₂CF₂CF₂—, or F₃C(CF₂)₃CF₂—,

Particularly preferred DPP compounds of the formula I are the followingcompounds: (I)

Compound A¹ = A² R¹ = R² A-1

A-2

A-3

A-4

A-5 ″

A-6 ″ —(CH₂)₃CH₃ A-7

A-8

—Si(CH₃)₃ A-9

A-10

A-11

A-12

A-13

A-14

A-15

A-16

A-17

—CH(CH₃)₂ A-18

A-19

A-20

A-21

A-22

A-23 ″

A-24 ″ —CF₃ A-25 ″ —CHF₂ A-26 ″ —CH₂F A-27 ″

A-28 ″

A-29 ″

A³ and A⁴ independently from each other stand for

wherein R⁵, R⁶, R⁸, R⁹, R¹⁶ and R¹⁷ have the above-defined meanings.

If AP and A⁴ independently from each other stand for a group of theformula

R⁵ and R⁶ are preferably hydrogen, R⁸ is preferably C₁-C₆alkyl or phenyland R¹⁶ and R¹⁷ are preferably hydrogen or phenyl.

If A³ and A⁴ independently from each other stand for a group of theformula

R⁵ and R⁶ are preferably hydrogen and R⁸ is preferably C₁-C₆alkyl orphenyl.

In particular A³ and A⁴ independently of each other stand for

wherein R⁵, R⁶, R⁷ independently from each other stand for hydrogen,C₁-C₈-alkyl, C₁-C₈-alkoxy, —OCR¹¹R¹²_(CH₂)_(m)-A⁵, cyano, chloro, —OR¹⁰,or phenyl, which can be substituted one to three times with C₁-C₈alkylor C₁-C₈alkoxy, wherein R¹⁰ stands for C₆-C₂₄-aryl, such as phenyl,1-naphthyl or 2-naphthyl, R¹¹ and R¹² are hydrogen or C₁-C₄-alkyl, m is0 or 1, A⁵ is phenyl, 1-naphthyl or 2-naphthyl, R⁸ and R⁹ independentlyfrom each other stand for hydrogen, C₁-C₈-alkyl, C₅-C₁₂-cycloalkyl, inparticular cyclohexyl, —CR¹¹R¹²—(CH₂)_(m)-A⁵, C₆-C₂₄-aryl, such asphenyl, 1-naphthyl, 2-naphthyl, 4-biphenyl, phenanthryl, terphenyl,pyrenyl, 2- or 9-fluorenyl or anthracenyl, preferably C₆-C₁₂aryl such asphenyl, 1-naphthyl, 2-naphthyl, 4-biphenyl, which may be unsubstitutedor substituted, in particular A¹, or a saturated or unsaturatedheterocyclic radical comprising five to seven ring atoms, wherein thering consists of carbon atoms and one to three hetero atoms selectedfrom the group consisting of nitrogen, oxygen and sulfur.

In particular groups of the following formula are preferred

wherein R⁸ and R⁹ are independently of each other a group of the formula

wherein R²′, R²² and R²³ are independently of each other hydrogen,C₁-C₈alkyl, a hydroxyl group, a mercapto group, C₁-C₈alkoxy,C₁-C₈alkylthio, halogen, halo-C₁-C₈alkyl, a cyano group, an aldehydegroup, a ketone group, a carboxyl group, an ester group, a carbamoylgroup, an amino group, a nitro group, a silyl group or a siloxanylgroup. Preferably R²¹, R²² and R²³ are independently of each otherhydrogen, C₁-C₈alkyl, C₁-C₈alkoxy or C₁-C₈alkylthio. Particularlypreferred DPP compounds of the formula II are the following compounds:(II)

Compound R³ = R⁴ R⁸ R⁹ B-1

B-2 —(CH₂)₃CH₃

B-3

B-4

B-5

″ ″ B-6 ″

B-7

B-8

B-9

Particularly preferred inventive compositions comprise compounds A-2 andB-1, A-2 and B-3, A-2 and B-7, A-11 and B-1 or A-11 and B-7.

The inventive DPP compounds of formula I or II can be synthesizedaccording to or in analogy to methods well known in the art, such asdescribed, for example, in U.S. Pat. No. 4,579,949, EP-A 353,184,EP-A-133,156, EP-A-1,087,005 and EP-A-1,087,006.

The term “halogen” means fluorine, chlorine, bromine and iodine.

C₁-C₂₅alkyl is typically linear or branched—where possible—methyl,ethyl, n-propyl, isopropyl, n-butyl, sec.-butyl, isobutyl, tert.-butyl,n-pentyl, 2-pentyl, 3-pentyl, 2,2-dimethylpropyl, n-hexyl, n-heptyl,n-octyl, 1,1,3,3-tetramethylbutyl and 2-ethylhexyl, n-nonyl, decyl,undecyl, dodecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl,octadecyl, eicosyl, heneicosyl, docosyl, tetracosyl or pentacosyl,preferably C₁-C₈alkyl such as methyl, ethyl, n-propyl, isopropyl,n-butyl, sec.-butyl, isobutyl, tert.-butyl, n-pentyl, 2-pentyl,3-pentyl, 2,2-dimethyl-propyl, n-hexyl, n-heptyl, n-octyl,1,1,3,3-tetramethylbutyl and 2-ethylhexyl, more preferably C₁-C₄alkylsuch as typically methyl, ethyl, n-propyl, isopropyl, n-butyl,sec.-butyl, isobutyl, tert.-butyl; C₁-C₃alkyl stands for methyl, ethyl,n-propyl, or isopropyl; C₁-C₆alkyl stands for methyl, ethyl, n-propyl,isopropyl, n-butyl, sec.-butyl, isobutyl, tert.-butyl, n-pentyl,2-pentyl, 3-pentyl, 2,2-dimethyl-propyl, or n-hexyl.

The “aldehyde group, ketone group, ester group, carbamoyl group andamino group” include those substituted by an aliphatic hydrocarbongroup, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, aheterocyclic group or the like, wherein the aliphatic hydrocarbon group,alicyclic hydrocarbon group, aromatic hydrocarbon group and heterocyclicgroup may be unsubstituted or substituted. The term “silyl group” meansa silicon compound group such as trimethylsilyl. The term “siloxanylgroup” means a silicon compound group linking through intermediation ofan ether linkage, such as trimethylsiloxanyl and the like.

Examples of C₁-C₈alkoxy are methoxy, ethoxy, n-propoxy, isopropoxy,n-butoxy, sec.-butoxy, isobutoxy, tert.-butoxy, n-pentoxy, 2-pentoxy,3-pentoxy, 2,2-dimethylpropoxy, n-hexoxy, n-heptoxy, n-octoxy,1,1,3,3-tetramethylbutoxy and 2-ethylhexoxy, preferably C₁-C₄alkoxy suchas typically methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy,sec.-butoxy, isobutoxy, tert.-butoxy. The term “alkylthio group” meansthe same groups as the alkoxy groups, except that the oxygen atom ofether linkage is replaced by a sulfur atom.

The term “aryl group” is typically C₆-C₂₄aryl, such as phenyl,1-naphthyl, 2-naphthyl, 4-biphenyl, phenanthryl, terphenyl, pyrenyl, 2-or 9-fluorenyl or anthracenyl, preferably C₆-C₁₂aryl such as phenyl,1-naphthyl, 2-naphthyl, 4-biphenyl, which may be unsubstituted orsubstituted.

The term “cycloalkyl group” is typically C₅-C₁₂cycloalkyl, such ascyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl,cyclodecyl, cycloundecyl, cyclododecyl, preferably cyclopentyl,cyclohexyl, cycloheptyl, or cyclooctyl, may be unsubstituted orsubstituted. The term “cycloalkenyl group” means an unsaturatedalicyclic hydrocarbon group containing one or more double bonds, such ascyclopentenyl, cyclopentadienyl, cyclohexenyl and the like, which may beunsubstituted or substituted. The cycloalkyl group, in particular acyclohexyl group, can be condensed one or two times by phenyl which canbe substituted one to three times with C₁-C₄-alkyl, halogen and cyano.Examples of such condensed cyclohexyl groups are:

in particular

wherein R²¹, R²²R²³, R²⁴, R²⁵ and R²⁶ are independently of each otherC₁-C₄-alkyl, halogen and cyano, in particular hydrogen. The term“heterocyclic radical” is a ring with five to seven ring atoms, whereinnitrogen, oxygen or sulfur are the possible hetero atoms, and istypically an unsaturated heterocyclic radical with five to 18 atomshaving at least six conjugated π-electrons such as thienyl,benzo[b]thienyl, dibenzo[b,d]thienyl, thianthrenyl, furyl, furfuryl,2H-pyranyl, benzofuranyl, isobenzofuranyl, dibenzofuranyl,phenoxythienyl, pyrrolyl, imidazolyl, pyrazolyl, pyridyl, bipyridyl,triazinyl, pyrimidinyl, pyrazinyl, pyridazinyl, indolizinyl, isoindolyl,indolyl, indazolyl, purinyl, quinolizinyl, chinolyl, isochinolyl,phthalazinyl, naphthyridinyl, chinoxalinyl, chinazolinyl, cinnolinyl,pteridinyl, carbazolyl, carbolinyl, benzotriazolyl, benzoxazolyl,phenanthridinyl, acridinyl, perimidinyl, phenanthrolinyl, phenazinyl,isothiazolyl, phenothiazinyl, isoxazolyl, furazanyl or phenoxazinyl,preferably the above-mentioned mono- or bicyclic heterocyclic radicals.

The above-mentioned substituents can be substituted by a C₁-C₈alkyl, ahydroxyl group, a mercapto group, C₁-C₈alkoxy, C₁-C₈alkylthio, halogen,halo-C₁-C₈alkyl, a cyano group, an aldehyde group, a ketone group, acarboxyl group, an ester group, a carbamoyl group, an amino group, anitro group, a silyl group or a siloxanyl group,

The present invention relates further to an electroluminescent devicehaving the composition according to the present invention between ananode and a cathode and emitting light by the action of electricalenergy.

Typical constitutions of latest organic electroluminescent devices are:

-   (i) an anode/a hole transporting layer/an electron transporting    layer/a cathode, in which the compositions are used either as    positive-hole transport composition, which is exploited to form the    light emitting and hole transporting layers, or as electron    transport compositions, which can be exploited to form the    light-emitting and electron transporting layers, and-   (ii) an anode/a hole transporting layer/a light-emitting layer/an    electron transporting layer/a cathode, in which the compositions    form the light-emitting layer regardless of whether they exhibit    positive-hole or electron transport properties in this constitution,    and-   (iii) an anode/a hole injection layer/a hole transporting layer/a    light-emitting layer/an electron transporting layer/a cathode, and-   (iv) an anode/a hole transporting layer/a light-emitting layer/a    positive hole inhibiting layer/an electron transporting layer/a    cathode, and-   (v) an anode/a hole injection layer/a hole transporting layer/a    light-emitting layer/a positive hole inhibiting layer/an electron    transporting layer/a cathode.

Thin film type electroluminescent devices usually consist essentially ofa pair of electrodes and at least one charge transporting layer inbetween. Usually two charge transporting layers, a hole transportinglayer (next to the anode) and an electron transporting layer (next tothe cathode) are present. Either one of them contains—depending on itsproperties as hole-transporting or electron-transporting material—aninorganic or organic fluorescence substance as light-emitting material.It is also common, that a light-emitting material is used as anadditional layer between the hole-transporting and theelectron-transporting layer. In the above mentioned device structure, ahole injection layer can be constructed between a anode and a holetransporting layer and/or a positive hole inhibiting layer can beconstructed between a light emitting layer and a electron transportinglayer to maximise hole and electron population in the light emittinglayer, reaching large efficiency in charge recombination and intensivelight emission.

The devices can be prepared in several ways. Usually, vacuum evaporationis used for the preparation. Preferably, the organic layers arelaminated in the above order on a commercially availableindium-tin-oxide (“ITO”) glass substrate held at room temperature, whichworks as the anode in the above constitutions. The membrane thickness ispreferably in the range of 1 to 10,000 nm, more preferably 1 to 5,000nm, more preferably 1 to 1,000 nm, more preferably 1 to 500 nm. Thecathode metal, such as a Mg/Ag alloy or a binary Li—Al system of ca. 200nm is laminated on the top of the organic layers. The vacuum during thedeposition is preferably less than 0.1333 Pa (1×10⁻³ Torr), morepreferably less than 1.333×10⁻³ Pa (1×10⁻⁵ Torr), more preferably lessthan 1.333×10⁻⁴ Pa (1×10⁻⁶ Torr).

As anode usual anode materials which possess high work function such asmetals like gold, silver, copper, aluminum, indium, iron, zinc, tin,chromium, titanium, vanadium, cobalt, nickel, lead, manganese, tungstenand the like, metallic alloys such as magnesium/copper,magnesium/silver, magnesium/aluminum, aluminum/indium and the like,semiconductors such as Si, Ge, GaAs and the like, metallic oxides suchas indium-tin-oxide (“ITO”), ZnO and the like, metallic compounds suchas CuI and the like, and furthermore, electroconducting polymers suchpolyacetylene, polyaniline, polythiophene, polypyrrole,polyparaphenylene and the like, preferably ITO, most preferably ITO onglass as substrate can be used.

Of these electrode materials, metals, metallic alloys, metallic oxidesand metallic compounds can be transformed into electrodes, for example,by means of the sputtering method. In the case of using a metal or ametallic alloy as a material for an electrode, the electrode can beformed also by the vacuum deposition method. In the case of using ametal or a metallic alloy as a material forming an electrode, theelectrode can be formed, furthermore, by the chemical plating method(see for example, Handbook of Electrochemistry, pp 383-387, Mazuren,1985). In the case of using an electroconducting polymer, an electrodecan be made by forming it into a film by means of anodic oxidationpolymerization method onto a substrate which is previously provided withan electroconducting coating. The thickness of an electrode to be formedon a substrate is not limited to a particular value, but, when thesubstrate is used as a light emitting plane, the thickness of theelectrode is preferably within the range of from 1 nm to 100 nm, morepreferably, within the range of from 5 to 50 nm so as to ensuretransparency.

In a preferred embodiment ITO is used on a substrate having an ITO filmthickness in the range of from 10 nm (100 Å) to 1μ (10000 Å), preferablyfrom 20 nm (200 Å) to 500 nm (5000 Å). Generally, the sheet resistanceof the ITO film is chosen in the range of not more than 100 Ω/cm²,preferably not more than 50 Ω/cm².

Such anodes are commercially available from Japanese manufacturers, suchas Geomatech Co. Ltd., Sanyo Vacuum Co. Ltd., Nippon Sheet Glass Co.Ltd.

As substrate either an electronconducting or electrically insulatingmaterial can be used. In case of using an electroconducting substrate, alight emitting layer or a positive hole transporting layer is directlyformed thereupon, while in case of using an electrically insulatingsubstrate, an electrode is firstly formed thereupon and then a lightemitting layer or a positive hole transporting layer is superposed.

The substrate may be either transparent, semi-transparent or opaque.However, in case of using a substrate as an indicating plane, thesubstrate must be transparent or semi-transparent.

Transparent electrically insulating substrates are, for example,inorganic compounds such as glass, quartz and the like, organicpolymeric compounds such as polyethylene, polypropylene,polymethylmethacrylate, polyacrylonitrile, polyester, polycarbonate,polyvinylchloride, polyvinylalcohol, polyvinylacetate and the like. Eachof these substrates can be transformed into a transparentelectroconducting substrate by providing it with an electrode accordingto one of the methods described above.

Examples of semi-transparent electrically insulating substrates areinorganic compounds such as alumina, YSZ (yttrium stabilized zirconia)and the like, organic polymeric compounds such as polyethylene,polypropylene, polystyrene, epoxy resins and the like. Each of thesesubstrates can be transformed into a semi-transparent electroconductingsubstrate by providing it with an electrode according to one of theabovementioned methods.

Examples of opaque electroconducting substrates are metals such asaluminum, indium, iron, nickel, zinc, tin, chromium, titanium, copper,silver, gold, platinum and the like, various elctroplated metals,metallic alloys such as bronze, stainless steel and the like,semiconductors such as Si, Ge, GaAs, and the like, electroconductingpolymers such as polyaniline, polythiophene, polypyrrole, polyacetylene,polyparaphenylene and the like.

A substrate can be obtained by forming one of the above listed substratematerials to a desired dimension. It is preferred that the substrate hasa smooth surface. Even if it has a rough surface, it will not cause anyproblem for practical use, provided that it has round unevenness havinga curvature of not less than 20 μm. As for the thickness of thesubstrate, there is no restriction as far as it ensures sufficientmechanical strength. As cathode usual cathode materials which possesslow work function such as alkali metals, earth alkaline metals, group 13elements, silver, and copper as well as alloys or mixtures thereof suchas sodium, lithium, potassium, sodium-potassium alloy, magnesium,magnesium-silver alloy, magnesium-copper alloy, magnesium-aluminumalloy, magnesium-indium alloy, aluminum, aluminum-aluminum oxide alloy,aluminum-lithium alloy, indium, calcium, and materials exemplified inEP-A 499,011 such as electroconducting polymers e.g. polypyrrole,polythiophene, polyaniline, polyacetylene etc., preferably Mg/Ag alloys,or Li—Al compositions can be used.

In a preferred embodiment a magnesium-silver alloy or a mixture ofmagnesium and silver, or a lithium-aluminum alloy or a mixture oflithium and aluminum can be used in a film thickness in the range offrom 10 nm (100 Å) to 1 μm (10000 Å), preferably from 20 nm (200 Å) to500 nm (5000 Å).

Such cathodes can be deposited on the foregoing electron transportinglayer by known vacuum deposition techniques described above.

In a preferred ambodiment of this invention a light-emitting layer canbe used between the hole transporting layer and the electrontransporting layer. Usually the light-emitting layer is prepared byforming a thin film on the hole transporting layer.

As methods for forming said thin film, there are, for example, thevacuum deposition method, the spin-coating method, the casting method,the Langmuir-Blodgett (“LB”) method and the like. Among these methods,the vacuum deposition method, the spin-coating method and the castingmethod are particularly preferred in view of ease of operation and cost.

In case of forming a thin film using a composition by means of thevacuum deposition method, the conditions under which the vacuumdeposition is carried out are usually strongly dependent on theproperties, shape and crystalline state of the compound(s). However,optimum conditions are usually as follows: temperature of the heatingboat: 100 to 400° C.; substrate temperature: −100 to 350° C.; pressure:1.33×10⁴ Pa (1×10² Torr) to 1.33×10⁻⁴ Pa (1×10⁻⁶ Torr) and depositionrate: 1 pm to 6 nm/sec.

In an organic EL element, the thickness of the light emitting layer isone of the factors determining its light emission properties. Forexample, if a light emitting layer is not sufficiently thick, a shortcircuit can occur quite easily between two electrodes sandwiching saidlight emitting layer, and therefor, no EL emission is obtained. On theother hand, if the light emitting layer is excessively thick, a largepotential drop occurs inside the light emitting layer because of itshigh electrical resistance, so that the threshold voltage for ELemission increases. Accordingly, the thickness of the organic lightemitting layer is limited to the range of from 5 nm to 5 μm, preferablyto the range of from 10 nm to 500 nm.

In the case of forming a light emitting layer by using the spin-coatingmethod and the casting method, the coating can be carried out using asolution prepared by dissolving the composition in a concentration offrom 0.0001 to 90% by weight in an appropriate organic solvent such asbenzene, toluene, xylene, tetrahydrofurane, methyltetrahydrofurane,N,N-dimethylformamide, dichloromethane, dimethylsulfoxide and the like.If the concentration exceeds 90% by weight, the solution usually is soviscous that it no longer permits forming a smooth and homogenous film.On the other hand, if the concentration is less than 0.0001% by weight,the efficiency of forming a film is too low to be economical.Accordingly, a preferred concentration of the composition is within therange of from 0.01 to 80% by weight. In the case of using the abovespin-coating or casting method, it is possible to further improve thehomogeneity and mechanical strength of the resulting layer by adding apolymer binder to the solution for forming the light emitting layer. Inprinciple, any polymer binder may be used, provided that it is solublein the solvent in which the composition is dissolved. Examples of suchpolymer binders are polycarbonate, polyvinylalcohol, polymethacrylate,polymethylmethacrylate, polyester, polyvinylacetate, epoxy resin and thelike. However, if the solid content composed of the polymer binder andthe composition exceeds 99% by weight, the fluidity of the solution isusually so low that it is impossible to form a light emitting layerexcellent in homogeneity. On the other hand, if the content of thecomposition is substantially smaller than that of the polymer binder,the electrical resistance of said layer is very large, so that it doesnot emit light unless a high voltage is applied thereto. Accordingly,the preferred ratio of the polymer binder to the composition is chosenwithin the range of from 10:1 to 1:50 by weight, and the solid contentcomposed of both components in the solution is preferably within therange of from 0.01 to 80% by weight, and more preferably, within therange of 0.1 to 60% by weight.

As hole-transporting layers known organic hole transporting compoundssuch as polyvinyl carbazole

a TPD compound disclosed in J. Amer. Chem. Soc. 90 (1968) 3925:

wherein Q₁ and Q₂ each represent a hydrogen atom or a methyl group; acompound disclosed in J. Appl. Phys. 65(9) (1989) 3610:

a stilbene based compound

wherein T and T₁ stand for an organic radical;

-   a hydrazone based compound    wherein Rx, Ry and Rz stand for an organic radical, and the like can    be used.

Compounds to be used as a positive hole transporting material are notrestricted to the above listed compounds. Any compound having a propertyof transporting positive holes can be used as a positive holetransporting material such as-triazole derivatives, oxadiazolederivatives, imidazole derivatives, polyarylalkane derivatives,pyrazoline derivative, pyrazolone derivatives, phenylene diaminederivatives, arylamine derivatives, amino substituted chalconederivatives, oxazole derivatives, stilbenylanthracene derivatives,fluorenone derivatives, hydrazone derivatives, stilbene derivatives,copolymers of aniline derivatives, electro-conductive oligomers,particularly thiophene oligomers, porphyrin compounds, aromatic tertiaryamine compounds, stilbenyl amine compounds etc. Particularly, aromatictertiary amine compounds such asN,N,N′,N′-tetraphenyl-4,4′-diaminobiphenyl,N,N′-diphenyl-N,N′-bis(3-methylphenyl)-4,4′-diaminobiphenyl (TPD),2,2′-bis(di-p-torylaminophenyl)propane,1,1′-bis(4-di-torylaminophenyl)-4-phenylcyclohexane,bis(4-dimethylamino-2-methylphenyl)phenylmethane,bis(4-di-p-tolylaminophenyl)phenyl-methane,N,N′-diphenyl-N,N′-di(4-methoxyphenyl)-4,4′-diaminobiphenyl,N,N,N′,N′-tetraphenyl-4,4′-diaminodiphenylether,4,4′-bis(diphenylamino)quaterphenyl, N,N,N-tri(p-tolyl)amine,4-(di-p-tolylamino)-4′-[4-(di-p-tolylamino)stilyl]stilbene,4-N,N-diphenylamino-(2-diphenylvinyl)benzene,3-methoxy-4′-N,N-diphenylaminostilbene, N-phenylcarbazole etc. are used.

Furthermore, 4,4′-bis[N-(1-naphtyl)-N-phenylamino]biphenyl disclosed inU.S. Pat. No. 5,061,569 and the compounds disclosed in EP-A 508,562, inwhich three triphenylamine units are bound to a nitrogen atom, such as4,4′,4″-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine, can beused.

A positive hole transporting layer can be formed by preparing an organicfilm containing at least one positive hole transporting material on theanode. The positive hole transporting layer can be formed by the vacuumdeposition method, the spin-coating method, the casting method, the LBmethod and the like. Of these methods, the vacuum deposition method, thespin-coating method and the casting method are particularly preferred inview of ease and cost.

In the case of using the vacuum deposition method, the conditions fordeposition may be chosen in the same manner as described for theformation of a light emitting layer (see above). If it is desired toform a positive hole transporting layer comprising more than onepositive hole transporting material, the coevaporation method can beemployed using the desired compounds.

In the case of forming a positive hole transporting layer by thespin-coating method or the casting method, the layer can be formed underthe conditions described for the formation of the light emitting layer(see above).

As in the case of forming the light emitting layer a smoother and morehomogeneous positive hole transporting layer can be formed by using asolution containing a binder and at least one positive hole transportingmaterial. The coating using such a solution can be performed in the samemanner as described for the light emitting layer. Any polymer binder maybe used, provided that it is soluble in the solvent in which the atleast one positive hole transporting material is dissolved. Examples ofappropriate polymer binders and of appropriate and preferredconcentrations are given above when describing the formation of a lightemitting layer.

The thickness of the positive hole transporting layer is preferablychosen in the range of from 0.5 to 1000 nm, preferably from 1 to 100 nm,more preferably from 2 to 50 nm.

As hole injection materials known organic hole transporting compoundssuch as metal-free phthalocyanine (H₂Pc), copper-phthalocyanine (Cu—Pc)and their derivatives as described, for example, in JP64-7635 can beused. Furthermore, some of the aromatic amines defined as holetransporting materials above, which have a lower ionisation potentialthan the hole transporting layer, can be used.

A hole injection layer can be formed by preparing an organic filmcontaining at least one hole injection material between the anode layerand hole transporting layer. The hole injection layer can be formed bythe vacuum deposition method, the spin-coating method, the castingmethod, the LB method and the like. The thickness of the layer ispreferably from 5 nm to 5 μm, and more preferably from 10 nm to 100 nm.

The electron transporting materials should have a high electroninjection efficiency (from the cathode) and a high electron mobility.The following materials can be exemplified for electron transportingmaterials: tris(8-hydroxyquinolinato)-aluminum(III) and its derivatives,bis(10-hydroxybenzo[h]quinolinolato)beryllium(II) and its derivatives,oxadiazole derivatives, such as2-(4-biphenyl)-5-(4-tert.-butylphenyl)-1,3,4-oxadiazole and its dimersystems, such as1,3-bis(4-tert.-butylphenyl-1,3,4)oxadiazolyl)biphenylene and1,3-bis(4-tert.-butylphenyl-1,3,4-oxadiazolyl)phenylene, dioxazolederivatives, triazole derivatives, coumarine derivatives,imidazopyridine derivatives, phenanthroline derivatives or perylenetetracarboxylic acid derivatives disclosed in Appl. Phys. Lett. 48 (2)(1986) 183.

An electron transporting layer can be formed by preparing an organicfilm containing at least one electron transporting material on the holetransporting layer or on the light-emitting layer. The electrontransporting layer can be formed by the vacuum deposition method, thespin-coating method, the casting method, the LB method and the like.

It is preferred that the positive hole inhibiting materials for apositive hole inhibiting layer have high electron injection/transportingefficiency from the electron transporting layer to the light emissionlayer and also have higher ionisation potential than the light emittinglayer to prevent the flowing out of positive holes from the lightemitting layer to avoid a drop in luminescence efficiency.

As the positive hole inhibiting material known materials, such as Balq,TAZ and phenanthroline derivatives, e.g. bathocuproine (BCP), can beused:

The positive hole inhibiting layer can be formed by preparing an organicfilm containing at least one positive hole inhibiting material betweenthe electron transporting layer and the light-emitting layer. Thepositive hole inhibiting layer can be formed by the vacuum depositionmethod, the spin-coating method, the casting method, the LB method andthe like. The thickness of the layer preferably is chosen within therange of from 5 nm to 2 μM, and more preferably, within the range offrom 10 nm to 100 nm.

As in the case of forming a light emitting layer or a positive holetransporting layer, a smoother and more homogeneous electrontransporting layer can be formed by using a solution containing a binderand at least one electron transporting material.

The thickness of an electron transporting layer is preferably chosen inthe range of from 0.5 to 1000 nm, preferably from 1 to 100 nm, morepreferably from 2 to 50 nm.

The light-emitting compositions have a fluorescence emission maximum inthe range of from 500 to 780, preferably from 520 to 750, more preferredfrom 540 to 700 nm. Further, the inventive compounds preferably exhibitan absorption maximum in the range of 450 to 580 nm.

The light-emitting compositions usually exhibit a fluorescence quantumyield (“FQY”) in the range of from 1>FQY≧0.3 (measured in aeratedtoluene or DMF). Further, in general, the inventive compositions exhibita molar absorption coefficient in the range of from 5000 to 100000.

Another embodiment of the present invention relates to a method ofcoloring high molecular weight organic materials (having a molecularweight usually in the range of from 10³ to 10⁷ g/mol; comprisingbiopolymers, and plastic materials, including fibres) by incorporatingtherein the inventive composition by methods known in the art.

The inventive compositions can be used, as described for the DPPcompounds of formula I′ in EP-A-1087005, for the preparation of

-   inks, for printing inks in printing processes, for flexographic    printing, screen printing, packaging printing, security ink    printing, intaglio printing or offset printing, for pre-press stages    and for textile printing, for office, home applications or graphics    applications, such as for paper goods, for example, for ballpoint    pens, felt tips, fiber tips, card, wood, (wood) stains, metal,    inking pads or inks for impact printing processes (with    impact-pressure ink ribbons), for the preparation of-   colorants, for coating materials, for industrial or commercial use,    for textile decoration and industrial marking, for roller coatings    or powder coatings or for automotive finishes, for high-solids    (low-solvent), water-containing or metallic coating materials or for    pigmented formulations for aqueous paints, for the preparation of-   pigmented plastics for coatings, fibers, platters or mold carriers,    for the preparation of-   non-impact-printing material for digital printing, for the thermal    wax transfer printing process, the ink jet printing process or for    the thermal transfer printing process, and also for the preparation    of-   color filters, especially for visible light in the range from 400 to    700 nm, for liquid-crystal displays (LCDs) or charge combined    devices (CCDs) or for the preparation of-   cosmetics or for the preparation of-   polymeric ink particles, toners, dye lasers, dry copy toners liquid    copy toners, or electrophotographic toners, and electroluminescent    devices.

Another preferred embodiment concerns the use of the inventivecompositions for color changing media. There are three major techniquesin order to realize full-color organic electroluminescent devices:

-   (i) use of the three primary colors blue, green and red generated by    electroluminescence,-   (ii) conversion of the electroluminescent blue or white to    photoluminescent green and red via color changing media (CCM), which    absorb the above electroluminescent blue, and fluorescence in green    and red.-   (iii) conversion of the white luminescent emission to blue, green    and red via color filters.

The inventive compounds are useful for EL materials for the abovecategory (i) and, in addition, for the above mention technique (ii).This is because the invented combinations of compounds can exhibitstrong photoluminescence as well as electrolunimescence.

Technique (ii) is, for example, known from U.S. Pat. No. 5,126,214,wherein EL blue with a maximum wavelength of ca. 470-480 nm is convertedto green and red using coumarin,4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran,pyridine, rhodamine 6G, phenoxazone or other dyes.

Illustrative examples of suitable organic materials of high molecularweight which can be colored with the inventive compositions aredescribed in EP-A-1087005.

Particularly preferred high molecular weight organic materials, inparticular for the preparation of a paint system, a printing ink or ink,are, for example, cellulose ethers and esters, e.g. ethylcellulose,nitrocellulose, cellulose acetate and cellulose butyrate, natural resinsor synthetic resins (polymerization or condensation resins) such asaminoplasts, in particular urea/formaldehyde and melamine/formaldehyderesins, alkyd resins, phenolic plastics, polycarbonates, polyolefins,polystyrene, polyvinyl chloride, polyamides, polyurethanes, polyester,ABS, ASA, polyphenylene oxides, vulcanized rubber, casein, silicone andsilicone resins as well as their possible mixtures with one another.

It is also possible to use high molecular weight organic materials indissolved form as film formers, for example boiled linseed oil,nitrocellulose, alkyd resins, phenolic resins, melamine/formaldehyde andurea/formaldehyde resins as well as acrylic resins.

Said high molecular weight organic materials may be obtained singly orin admixture, for example in the form of granules, plastic materials,melts or in the form of solutions, in particular for the preparation ofspinning solutions, paint systems, coating materials, inks or printinginks.

In a particularly preferred embodiment of this invention, the inventivecompositions are used for the mass coloration of polyvinyl chloride,polyamides and, especially, polyolefins such as polyethylene andpolypropylene as well as for the preparation of paint systems, includingpowder coatings, inks, printing inks, color filters and coating colors.

Illustrative examples of preferred binders for paint systems arealkyd/melamine resin paints, acryl/melamine resin paints, celluloseacetate/cellulose butyrate paints and two-pack system lacquers based onacrylic resins which are crosslinkable with polyisocyanate.

According to observations made to date, the inventive compositions canbe added in any desired amount to the material to be coloured, dependingon the end use requirements.

Hence, another embodiment of the present invention relates to acomposition comprising

-   (a) 0.01 to 50, preferably 0.01 to 5, particularly preferred 0.01 to    2% by weight, based on the total weight of the coloured high    molecular organic material, of a composition according to the    present invention, and-   (b) 99.99 to 50, preferably 99.99 to 95, particularly preferred    99.99 to 98% by weight, based on the total weight of the coloured    high molecular organic material, of a high molecular organic    material, and-   (c) optionally, customary additives such as rheology improvers,    dispersants, fillers, paint auxiliaries, siccatives, plasticizers,    UV-stabilizers, and/or additional pigments or corresponding    precursors in effective amounts, such as e.g. from 0 to 50% by    weight, based on the total weight of (a) and (b).

To obtain different shades, the inventive fluorescent DPP compounds offormula I may advantageously be used in admixture with fillers,transparent and opaque white, colored and/or black pigments as well ascustomary luster pigments in the desired amount.

For the preparation of paints systems, coating materials, color filters,inks and printing inks, the corresponding high molecular weight organicmaterials, such as binders, synthetic resin dispersions etc. and theinventive compositions are usually dispersed or dissolved together, ifdesired together with customary additives such as dispersants, fillers,paint auxiliaries, siccatives, plasticizers and/or additional pigmentsor pigment precursors, in a common solvent or mixture of solvents. Thiscan be achieved by dispersing or dissolving the individual components bythemselves, or also several components together, and only then bringingall components together, or by adding everything together at once.

Hence, a further embodiment of the present invention relates to a methodof using the inventive compositions for the preparation of dispersionsand the corresponding dispersions, and paint systems, coating materials,color filters, inks and printing inks comprising the inventivecompositions.

A particularly preferred embodiment relates to the use of the inventivecompositions for the preparation of fluorescent tracers for e.g. leakdetection of fluids such as lubricants, cooling systems etc., as well asto fluorescent tracers or lubricants comprising the inventivecompositions.

For the pigmentation of high molecular weight organic material, theinventive compositions, optionally in the form of masterbatches, aremixed with the high molecular weight organic materials using roll mills,mixing apparatus or grinding apparatus. Generally, the pigmentedmaterial is subsequently brought into the desired final form byconventional processes, such as calandering, compression molding,extrusion, spreading, casting or injection molding.

For pigmenting lacquers, coating materials and printing inks the highmolecular weight organic materials and the inventive compositions, aloneor together with additives, such as fillers, other pigments, siccativesor plasticizers, are generally dissolved or dispersed in a commonorganic solvent or solvent mixture. In this case it is possible to adopta procedure whereby the individual components are dispersed or dissolvedindividually or else two or more are dispersed or dissolved together andonly then are all of the components combined.

The present invention additionally relates to inks comprising acoloristically effective amount of the pigment dispersion of theinventive compositions.

The weight ratio of the pigment dispersion to the ink in general ischosen in the range of from 0.001 to 75% by weight, preferably from 0.01to 50% by weight, based on the overall weight of the ink.

The preparation and use of color filters or color-pigmented highmolecular weight organic materials are well-known in the art anddescribed e.g. in Displays 14/2, 1151 (1993), EP-A 784085, or GB-A2,310,072.

The color filters can be coated for example using inks, especiallyprinting inks, which can comprise pigment dispersions comprising theinventive compositions or can be prepared for example by mixing apigment dispersion comprising an inventive composition with chemically,thermally or photolytically structurable high molecular weight organicmaterial (so-called resist). The subsequent preparation can be carriedout, for example, in analogy to EP-A 654 711 by application to asubstrate, such as a LCD (liquid crystal display), subsequentphotostructuring and development.

Particular preference for the production of color filters is given topigment dispersions comprising an inventive composition which possessnon-aqueous solvents or dispersion media for polymers.

The present invention relates, moreover, to toners comprising a pigmentdispersion containing an inventive composition or a high molecularweight organic material pigmented with an inventive composition in acoloristically effective amount.

The present invention additionally relates to colorants, coloredplastics, polymeric ink particles, or non-impact-printing materialcomprising an inventive composition, preferably in the form of adispersion, or a high molecular weight organic material pigmented withan inventive composition in a coloristically effective amount.

A coloristically effective amount of the pigment dispersion according tothis invention comprising an inventive composition denotes in generalfrom 0.0001 to 99.99% by weight, preferably from 0.001 to 50% by weightand, with particular preference, from 0.01 to 50% by weight, based onthe overall weight of the material pigmented therewith.

The inventive compositions can be applied to colour polyamides, becausethey do not decompose during the incorporation into the polyamides.Further, they exhibit an exceptionally good lightfastness, a superiorheat stability, especially in plastics.

The organic EL device of the present invention has significantindustrial values since it can be adapted for a flat panel display of anon-wall television set, a flat light-emitting device, a light source fora copying machine or a printer, a light source for a liquid crystaldisplay or counter, a display signboard and a signal light. Thecompositions of the present invention can be used in the fields of anorganic EL device, an electrophotographic photoreceptor, a photoelectricconverter, a solar cell, an image sensor, and the like.

The following examples illustrate various embodiments of the presentinvention, but the scope of the invention is not limited thereto. In theexamples the “parts” denote “parts by weight” and the “percentages”denote “percentages by weight”, unless otherwise stated.

EXAMPLES Example 1

2.03 g (6.4 mmol) of 1,4-diketo-3,6-bis(4-metrhylphenyl)pyrrolopyrroleare slurred in 1-methyl 2-pyrrolidinone for 2 hours at room temperature.1.31 g (11.53 mmol) of potassium t-butoxide are added to the slurryunder nitrogen. After stirring for 2 hours, 20.5 g (11.1 mmol) of1-bromoethylbenzene are added to the reaction mixture and agitatedadditional 2 hours. Then, the mixture is poured into 50 ml of water andthe precipitate is collected by filtration and purified by columnchromatography (silica gel, dichloromethane as eluent), followed bywashing with methanol. After drying 780 mg of a fluorescent orange solidis obtained (mp.=262° C., yield: 24%).

Example 2

Example 1 was repeated except that1,4-diketo-3,6-bis(1-naphtyl)-pyrrolo-(3,4-c)-pyrrole was used asstarting material. Orange solid (mp.=263° C., yield: 32%).

Example 3

(1.0 mmol) of2,5-di-benzyl-1,4-diketo-3,6-(4-bromophenyl)pyrrolo(3,4,-c)pyrrole, 2.5mmol of di-tolylamine, 5 mg of Palladium(II)acetate, 1 mg oftert-butylphosphine and 50 ml of dry xylene were placed in a threenecked flask and stirred at 120° C. under nitrogen for 13 hours. Afterthe completion of the reaction xylene was removed under reduced pressureand the residue was purified by column chromatography (silica gel,dichloromethan as eluent). After drying 0.4 g of the desired product wasobtained as red solid (mp.=395° C.).

Example 4

Example 3 is repeated, except that2,5-di-butyl-1,4-diketo-3,6-(4-bromophenyl)pyrrolo(3,4-c)pyrrole is usedas starting material and bis(2-naphtyl)amine is used as reagent, wherebya red solid is obtained (mp.=222-224° C., yield: 46%).

Example 5

Example 3 is repeated, except that 2-naphtylphenylamine is used insteadof di-tolylamine, whereby a red solid is obtained (mp.=361° C., yield:53%).

Example 6

A glass substrate (manufactured by Asahi Glass Co., a product preparedby electron beam vapor deposition method) on which an ITO transparentelectroconductive film had been deposited up to a thickness of ca. 210nm is cut into a size of 30×40 mm, and etched. The substrate thusobtained is subjected to ultrasonic washing with acetone for 15 minutesand then to ultrasonic washing with Semikoklin 56 for 15 minutes, andthen washing with ultra-pure water. Subsequently, the substrate issubjected to ultrasonic washing with isopropyl alcohol for 15 minutes,dipped in hot methanol for 15 minutes, and then dried. Just beforeforming the substrate into an element, the substrate thus obtained issubjected to an UV-ozone treatment for one hour and placed in a vacuumvapour deposition apparatus, and the apparatus is evacuated until theinner pressure reached 1×10⁻⁵ Pa or less. Then, according to theresistance heating method,N,N′-diphenyl-N,N′-(3-methylphenyl)-1,1′-diphenyl-4,4′-diamine (TPD) isvapor-deposited as a positive hole transporting material up to athickness of 50 nm, to form a positive hole transporting layer.Subsequently, the DPP compounds obtained in example 1 (A-1) and example6 (B-4) are co-deposited as a light emitting layer up to a thickness of50 nm by controlling the ratio of deposition rate (A-1: B-4=99: ca. 1)to form an uniform light emitting layer. Subsequently, a Alq₃ layer isvapor-deposited to form an electron transporting layer having athickness of 50 nm. On top of that, a Mg—Ag alloy (10:1) isvapor-deposited to form a cathode having a thickness of 150 nm, wherebyan element having a size of 5×5 mm square is prepared.

The luminescent peak wavelength and emission intensity of theluminescent element thus obtained is summarized in Table 1.

Example 104 of EP-A-1087006 Example 7, 8, 9 and 10

Example 6 is repeated, except that the emitting material of example 6 isreplaced by the emitting materials as described in table 1. TABLE 1Emitting Material Compound of Compound of EL properties Device offormula I formula II Intensity Example [99 wt %] [ca. 1 wt %] Peak (nm)(cd/m2) Ex. 6 A-1 B-4 590 10980 Ex. 7 A-1 B-1 608 9026 Ex. 8 A-2 B-1 6109216 Ex. 9 A-2 B-2 594 6773 Ex. 10 A-2 B-3 600 12260 Reference A-3 — 5665260 Example 1 (100%) Reference A-1 — 534 2600 Example 2 (100%)

Example 11

Example 2 was repeated except that 3-(1-bromoethyl)-1-tert-butylbenzenewas used instead of 1-bromoethylbenzene. Orange solid (mp.=307° C.,yield: 18%).

Example 12

Example 2 was repeated except that 3-(1-bromoethyl)toluene was usedinstead of 1-bromoethylbenzene. Orange solid (mp.=243° C., yield: 14%).

Example 13

Example 2 was repeated except that 2-(1-bromoethyl)naphthalene was usedinstead of 1-bromoethylbenzene. Orange solid (mp.=325-329° C., yield:10%).

Example 14

Example 2 was repeated except that 1-(1-bromoethyl)naphthalene was usedinstead of 1-bromoethylbenzene. Orange solid (mp.=266° C., yield: 17%).

Example 15

Example 2 was repeated except that 4-bromo-1-(1-bromoethyl)benzene wasused instead of 1-bromoethylbenzene. Orange solid (mp.=223-225° C.,yield: 32%).

Example 16

Example 2 was repeated except that 4-phenyl-1-(1-bromoethyl)benzene wasused instead of 1-bromoethylbenzene. Orange solid (mp.=293° C., yield:16%).

Example 17

Example 2 was repeated except that isopropyl iodide was used instead of1-bromoethylbenzene. Orange solid (mp.=294-295° C., yield: 3%).

Example 18

Example 2 was repeated except that 1-bromo-1,2,3,4-tetrahydronaphthalenewas used instead of 1-bromoethylbenzene. Orange solid (mp.=360° C.,yield: 3%).

Example 19

Example 2 was repeated except that bromo d-phenyl methane was usedinstead of 1-bromoethylbenzene. Orange solid (mp.=258-266° C., yield:11%).

Example 20

Example 1 was repeated except that1,4-diketo-3,6-bis(1-phenanthrenyl)-pyrrolo-(3,4-c)-pyrrole was used asstarting material. Orange solid (mp.=326° C., yield: 4%).

Example 21

Example 3 was repeated except that2,5-bis-(4-cyanobenzyl)-1,4-diketo-3,6-(4-bromophenyl)pyrrolo(3,4,-c)pyrroleand 1,1′-bis(diphenylphosphino)ferrocene were used as a startingmaterial and Pd-ligand, respectively. Red violet solid (mp.=376° C.,yield: 45%).

Example 22

Example 16 was repeated except that2,5-bis-(4,5-di-cyanobenzyl)-1,4-diketo-3,6-(4-bromophenyl)pyrrolo(3,4,-c)pyrrolewas used as a starting material. Red violet solid (mp.=353-356° C.,yield: 17%).

Example 23

Example 4 was repeated except that benzylbromide was used instead ofiodobutane Red violet solid (mp.=359-361° C., yield: 12%).

Example 24-26

Example 6 is repeated, except that the emitting material of example 6 isreplaced by the emitting materials as described in table 2. TABLE 2Emitting Material Compound of Compound of EL properties Device offormula I formula II Intensity Example (wt %) (wt %) Peak (nm) (cd/m²)Ex. 24  A-2 (97.3) B-7 (2.7) 624 2717 Ex. 25 A-11 (97.5) B-1 (2.5) 6103996 Ex. 26 A-11 (97.3) B-7 (2.7) 614 5074

Example 27

Example 2 was repeated except that 2-(i-bromoethyl)toluene was usedinstead of 1-bromoethylbenzene. Yellow solid (mp.=276-278° C., yield:9%).

Reference Example 1

Example 8 is repeated, except that the compound below (A-3; Example 81of EP-A-1087006) is used as the light emitting material. The maximumluminance is 5260 Cd/m².

Reference Example 2

Example 6 is repeated, except that A-1 (Example 93 of EP-A-1087006) isused as the light emitting material. The maximum luminance thereof is2600 Cd/m².

As evident from the examples the composition of the present invention,comprising a DPP of the formula I and a DPP of the formula II, canprovide a luminescent element which is high in the efficiency ofelectrical energy utilisation and is characterized by a much higherluminance than the individual DPP compounds of formula I and II.

Example 28 Film Preparation of Color Changing Media

8 mg of A-2, 2 mg of B-7, 1 g of PMMA (Produced by Wako Pure ChemicalIndustries, Ltd.) are put in a bottle, and the mixture is dissolved in 5g of toluene. The solution is dropped on a slid glass substrate, andcoated on the glass by use of a spin coater with a rotating rate of 500rpm for 30 seconds. The obtained film is dried over 80° C. and a CCMfilm is obtained. The film is evaluated by use of fluorescencespectrophotometer F-4500 (Hitachi, Ltd.). When the film is irradiated byblue light with 470 nm, the film emits red light, the peak of whichlocates at 597 nm. Thus, the composition comprising the host and theguest is found to be applicable to CCM converting effectively blue lightinto red light.

1. A composition comprising a guest chromophore and a host chromophore,wherein the absorption spectrum of the guest chromophore overlaps withthe fluorescence emission spectrum of the host chromophore, wherein thehost chromophore is a diketopyrrolopyrrole having a photoluminescenceemission peak at 500 to 720 nm, and wherein the guest chromophore is adiketopyrrolopyrrole having an absorption peak at 500 to 720 nm.
 2. Acomposition according to claim 1, wherein the host chromophore is adiketopyrrolopyrrole (“DPP”) represented by formula I

and the guest chromophore is a DPP represented by formula II

wherein R¹, R², R³ and R⁴ independently from each other stand forC₁-C₂₅-alkyl, which can be substituted by fluorine, chlorine or bromine,C₅-C₁₂-cycloalkyl or C₅-C₁₂-cycloalkyl which can be condensed one or twotimes by phenyl which can be substituted one to three times withC₁-C₄-alkyl, halogen, nitro or cyano, silyl, A⁵ or CR¹¹R¹² (CH₂)_(m)-A⁵,wherein R¹¹ and R¹² independently from each other stand for hydrogen,fluorine, chlorine, bromine, cyano or C₁-C₄alkyl, which can besubstituted by fluorine, chlorine or bromine, or phenyl which can besubstituted one to three times with C₁-C₃alkyl, A⁵ stands for phenyl or1- or 2-naphthyl which can be substituted one to three times withC₁-C₈alkyl, C₁-C₈alkoxy, halogen, nitro, cyano, phenyl, which can besubstituted with C₁-C₈alkyl or C₁-C₈alkoxy one to three times, —NR¹³R¹⁴wherein R¹³ and R¹⁴ represent hydrogen, C₁-C₂₅-alkyl, C₅-C₁₂-cycloalkylor C₆-C₂₄-aryl, in particular phenyl or 1- or 2-naphthyl which can besubstituted one to three times with C₁-C₈alkyl, C₁-C₈alkoxy, halogen orcyano, or phenyl, which can be substituted with C₁-C₈alkyl orC₁-C₈alkoxy one to three times, and m stands for 0, 1, 2, 3 or 4, A¹ andA² independently from each other stand for

wherein R⁵, R⁶, R⁷ independently from each other stands for hydrogen,C₁-C₂₅-alkyl, C₁-C₂₅-alkoxy, —CR¹¹R¹²—(CH₂)_(m)-A⁵, cyano, halogen,—OR¹⁰, —S(O)_(p)R¹³, or phenyl, which can be substituted one to threetimes with C₁-C₈alkyl or C₁-C₈alkoxy, wherein R¹⁰ stands forC₆-C₂₄-aryl, or a saturated or unsaturated heterocyclic radicalcomprising five to seven ring atoms, wherein the ring consists of carbonatoms and one to three hetero atoms selected from the group consistingof nitrogen, oxygen and sulfur, R¹³ stands for C₁-C₂₅-alkyl,C₅-C₁₂-cycloalkyl, —CR¹¹R¹²_(CH₂)_(m)—Ph, R¹⁵ stands for C₆-C₂₄-aryl, pstands for 0, 1, 2 or 3 and n stands for 0, 1, 2, 3 or 4, A³ and A⁴independently from each other stand for

wherein R⁸ and R⁹ independently from each other stand for hydrogen,C₁-C₂₅-alkyl, C₅-C₁₂-cycloalkyl, —CR¹¹R¹²_(CH₂)_(m)-A⁵, C₆-C₂₄-aryl, inparticular A¹, or a saturated or unsaturated heterocyclic radicalcomprising five to seven ring atoms, wherein the ring consists of carbonatoms and one to three hetero atoms selected from the group consistingof nitrogen, oxygen and sulfur, and R¹⁶ and R¹⁷ are independently ofeach other hydrogen or C₆-C₂₄aryl.
 3. Composition according to claim 2,wherein A¹ and A² independently from each other stand for

wherein R⁵ is C₁-C₈-alkyl.
 4. Composition according to claim 2, whereinA³ and A⁴ independently from each other stand for

wherein R⁸ and R⁹ independently from each other stand for

wherein R⁵, R⁶, R⁷ independently from each other for hydrogen,C₁-C₈-alkyl or C₁-C₈-alkoxy.
 5. Composition according to claim 2,wherein R¹, R², R³ and R⁴ indendently from each other stand forC₁-C₈alkyl, C₅-C₁₂-cycloalkyl, which can be substituted one to threetimes with C₁-C₈alkyl and/or C₁-C₈alkoxy, phenyl or 1- or 2-naphthylwhich can be substituted one to three times with C₁-C₈alkyl and/orC₁-C₈alkoxy, or —CR¹¹R¹²(CH₂)_(m)-A⁵ wherein R¹¹ and R¹² stand forhydrogen, A⁵ stands for phenyl or 1- or 2-naphthyl, which can besubstituted one to three times with C₁-C₈alkyl and/or C₁-C₈alkoxy, and mstands for 0 or
 1. 6. Composition according to claim 2, wherein thecompound of the formula I is selected from the following compounds A-1to A-29: (I)

Compound A¹ = A² R¹ = R² A-1

A-2

A-3

A-4

A-5 ″

A-6 ″ —(CH₂)₃CH₃ A-7

A-8

—Si(CH₃)₃ A-9

A-10

A-11

A-12

A-13

A-14

A-15

A-16

A-17

—CH(CH₃)₂ A-18

A-19

A-20

A-21

A-22

A-23 ″

A-24 ″ —CF₃ A-25 ″ —CHF₂ A-26 ″ —CH₂F A-27 ″

A-28 ″

A-29 ″


7. Composition according to claim 2, wherein the compound of the formulaII is selected from the following compounds B-1 to B-9: (II)

Compound R³ = R⁴ R⁸ R⁹ B-1

B-2

B-3

B-4

B-5

″ ″ B-6 ″

B-7

B-8

B-9


8. An electroluminescent device comprising the composition according toclaim
 1. 9. An electroluminescent device according to claim 8,comprising in this order (a) an anode, (b) a hole transporting layer,(c) a light-emitting layer, (d) optionally an electron transportinglayer and (e) a cathode.
 10. A composition comprising (a) 0.01 to 50% byweight, based on the total weight of the colored high molecular weightorganic material, of the composition according to claim 1, and (b) 99.99to 50% by weight, based on the total weight of the colored highmolecular weight organic material, of a high molecular organic material.11. A method for coloring a high molecular weight organic material orand in color changing media by mixing a compostion according to claim 1with high molecular weight organic material or media compositions.
 12. Adiketopyrrolopyrrole (“DPP”) represented by formula I or II

wherein R¹, R², R³ and R⁴ independently from each other stand forC₁-C₂₅-alkyl, which can be substituted by fluorine, chlorine or bromine,C₅-C₁₂-cycloalkyl or C₅-C₁₂-cycloalkyl which can be condensed one or twotimes by phenyl which can be substituted one to three times withC₁-C₄-alkyl, halogen, nitro or cyano, silyl, A⁵ or —CR¹¹R¹²(CH₂)_(m)-A⁵, wherein R¹¹ and R¹² independently from each other standfor hydrogen, fluorine, chlorine, bromine, cyano or C₁-C₄alkyl, whichcan be substituted by fluorine, chlorine or bromine, or phenyl which canbe substituted one to three times with C₁-C₃alkyl, A⁵ stands for phenylor 1- or 2-naphthyl which can be substituted one to three times withC₁-C₈alkyl, C₁-C₈alkoxy, halogen, nitro, cyano, phenyl, which can besubstituted with C₁-C₈alkyl or C₁-C₈alkoxy one to three times, —NR¹³R¹⁴wherein R¹³ and R¹⁴ represent hydrogen, C₁-C₂₅-alkyl, C₅-C₁₂-cycloalkylor C₆-C₂₄-aryl, in particular phenyl or 1- or 2-naphthyl which can besubstituted one to three times with C₁-C₈alkyl, C₁-C₈alkoxy, halogen orcyano, or phenyl, which can be substituted with C₁-C₈alkyl orC₁-C₈alkoxy one to three times, and m stands for 0, 1, 2, 3 or 4, A¹ andA² independently from each other stand for

wherein R⁵, R⁶, R⁷ independently from each other stands for hydrogen,C₁-C₂₅-alkyl, C₁-C₂₅-alkoxy, —CR¹¹R¹²(CH₂)_(m)-A⁵, cyano, halogen,—OR¹⁰, —S(O)_(p)R¹³, or phenyl, which can be substituted one to threetimes with C₁-C₈alkyl or C₁-C₈alkoxy, wherein R¹⁰ stands forC₆-C₂₄-aryl, or a saturated or unsaturated heterocyclic radicalcomprising five to seven ring atoms, wherein the ring consists of carbonatoms and one to three hetero atoms selected from the group consistingof nitrogen, oxygen and sulfur, R¹³ stands for C₁-C₂₅-alkyl,C₅-C₁₂-cycloalkyl, —CR¹¹R¹²—(CH₂)_(m)—Ph, R¹⁵ stands for C₆-C₂₄-aryl, pstands for 0, 1, 2 or 3 and n stands for 0, 1, 2, 3 or 4, A³ and A⁴independently from each other stand for

wherein R⁸ and R⁹ independently from each other stand for hydrogen,C₁-C₂₅-alkyl, C₅-C₁₂cycloaolkyl, —CR¹¹R¹²(CH₂)_(m)-A⁵, C₆-C₂₄-aryl, inparticular A¹, or a saturated or unsaturated heterocyclic radicalcomprising five to seven ring atoms, wherein the ring consists of carbonatoms and one to three hetero atoms selected from the group consistingof nitrogen, oxygen and sulfur, and R¹⁶ and R¹⁷ are independently ofeach other hydrogen or C₆-C₂₄aryl.